docs: def show_frequencies(vid_data, fps, bounds=None):
      """Graph the average value of the video as well as the frequency strength"""
      averages = []
  
      if bounds:
          for x in range(1, vid_data.shape[0] - 1):
              averages.append(vid_data[x, bounds[2]:bounds[3], bounds[0]:bounds[1], :].sum())
      else:
          for x in range(1, vid_data.shape[0] - 1):
              averages.append(vid_data[x, :, :, :].sum())
  
      averages = averages - min(averages)
  
      charts_x = 1
      charts_y = 2
      pyplot.figure(figsize=(20, 10))
      pyplot.subplots_adjust(hspace=.7)
  
      pyplot.subplot(charts_y, charts_x, 1)
      pyplot.title("Pixel Average")
      pyplot.xlabel("Time")
      pyplot.ylabel("Brightness")
      pyplot.plot(averages)
  
      freqs = scipy.fftpack.fftfreq(len(averages), d=1.0 / fps)
      fft = abs(scipy.fftpack.fft(averages))
      idx = np.argsort(freqs)
  
      pyplot.subplot(charts_y, charts_x, 2)
      pyplot.title("FFT")
      pyplot.xlabel("Freq (Hz)")
      freqs = freqs[idx]
      fft = fft[idx]
  
      freqs = freqs[len(freqs) // 2 + 1:]
      fft = fft[len(fft) // 2 + 1:]
      pyplot.plot(freqs, abs(fft))
  
      pyplot.show()